When Majority Leader Kevin McCarthy entered the Ways and Means Committee room Thursday, almost everyone expected him to exit as the Republican nominee to be speaker. Instead, McCarthy shocked the conference and dropped out of a race he almost certainly would have won, prompting one obvious question: Why?

In a roughly five minute speech to his colleagues, McCarthy told members he did not want to be someone who divided the country. He said Republicans need someone who could unite them — and he simply wasn't that person. McCarthy had been under pressure since his now-infamous comments on the Benghazi Committee, but the astonishing announcement still baffled members. They were assembled in the Ways and Means Committee room to select the California Republican as their speaker-elect, after all, and now they were watching one of the most puzzling moves in the history of congressional politics.

Sources close to McCarthy said Thursday's withdrawal was a personal decision, that he didn't want to put his family through any turmoil. While the announcement was sudden, McCarthy apparently had wrestled with this decision for days.

McCarthy Drops Out of Race for Speaker

On Wednesday morning, Walter B. Jones, R-N.C., sent a letter to Republican Conference Chairwoman Cathy McMorris Rodgers, urging any speaker candidate to withdraw from the race "if there are any misdeeds he has committed since joining Congress that will embarrass himself, the Republican Conference, and the House of Representatives if they become public."

"Some of the most difficult times have been when our Republican leaders or potential Republican leaders must step down because of skeletons in their closets," Jones wrote, citing former Speaker Newt Gingrich, R-Ga., who left in 1999 amid rumors of infidelity, and former speaker-in-waiting Bob Livingston, R-La., who resigned the same year directly as a result of affairs .

On Thursday, Jones was one of the first Republicans out of the Ways and Means room — following right behind Speaker John A. Boehner and his staff as the Ohio Republican stormed out — and Jones told reporters he didn't know if McCarthy's decision had anything to do with his letter.

"I didn't ask it," Jones said. "I don't know. I don't know. I cannot tell you. I did the letter out of sincerity about saying — it had nothing to do with him — that we need to make sure that whoever we elect is a man of integrity and does not have anything that could be in his background."

Jones relayed McCarthy's message — that Republicans have a number of problems, that Republicans needed a new face to lead them, and that he was not that face — but he didn't say whether he bought that explanation.

Plenty of members did, however.

Trent Franks, R-Ariz., told reporters he had "nothing but the highest respect for that kind of statesmanship." Franks again recounted that McCarthy said he was stepping aside because he didn't think he could unite the party, and Franks said McCarthy was doing, "apart from all the political machinations," what he believed to be the right thing for the nation.

Another source close to McCarthy said the California Republican realized that even if he were able to bring 218 Republicans together, he would always have some members who wouldn't vote for him.

He would be living week-to-week, much the same way Boehner is ending his speakership: with a group of conservatives constantly threatening to bring him down. McCarthy realized, the source said, that Republicans need a new leader the entire conference could coalesce around.

That theory would seem to jibe with what Rep. Rich Nugent was hearing. The Florida Republican said he thought McCarthy was feeling "pressure from the House Freedom Caucus to do something" on rules and procedures.

Of course, conservatives were pushing for changes, but almost everyone in the conference assumed McCarthy was up to the challenge of placating the HFC and making the slog to 218 over the course of the next three weeks.

McCarthy was already a target on the right. He had been ridiculed on conservative talk radio, and tea party groups had taken to calling him "McBoehner" in recent days — giving the California Republican at least a glimpse of what might lay ahead.

That seemed to be Rep. Joe L. Barton's theory. The dean of the Texas delegation was emphatic that McCarthy had the votes and that he stepped aside "purely because of the nature of what's happened in the last week in some of the more conservative groups."

Barton mentioned that McCarthy's wife was with him in the room, and Barton thought this was something the two of them decided. "My personal opinion is it was Kevin McCarthy and his wife prayed about it last night — just like he said — and they decided to, in order to give somebody a chance to unify the Republican Conference, that he was going to withdraw his candidacy," Barton said.

McCarthy said he would stay in his position as majority leader, which would seem to run counter to any allegation that he wasn't running because of a scandal. But it is unclear why he would work for two weeks to secure the votes for speaker and then announce, at the very meeting where he is to be chosen speaker-in-waiting, that he is no longer running.

For now, many members seem to be taking McCarthy at his word. And a search for a new face begins.